Oahu

Oahu was the most populous island of the Hawaii chain, with about 200,000
inhabitants in 1941. Oahu was
also the
location of the major military facilities of the islands, including Pearl Harbor and
several airfields. The major
city and civilian port was Honolulu.
The only
important military base in Hawaii outside of Oahu was the alternate
fleet
anchorage at Lahaina.

In addition to the naval and air bases, the island was garrisoned by 24 and 25
Divisions and 34
Engineer Regiment. The two divisions were Regular Army formations
that were as well trained and equipped as any in the U.S. Army in 1941.